Analog driver controls used, for example, to operate the actuators of deformable mirrors use a drive amplifier with a feedback circuit to provide the required voltage to the actuators. There may be N addressable actuators. An input signal address—synchronized with a particular actuator is delivered by the drive amplifier through an N-channel power mux which applies that input signal to the addressed one of N actuators. A feedback mux simultaneously synchronizes the switching of the feedback circuit with the addressable actuator. A typical mux is one such as a Model No. 20207 available form Supertex of Sunnyvale, Calif.
Ideally each actuator will hold its charge as established by the input provided through the power mux at least until the next time it is again addressed with an input. However, some leakage occurs through the open channels of the power mux so that the proper charge/voltage is not maintained on the actuators and the shape of the deformable mirror is compromised.